1. Field of the Invention
The present invention relates to a keyboard and electronic equipment.
2. Description of the Related Art
A keyboard is an information input device that is widely used in electronic equipment such as a desktop personal computer, a laptop personal computer, a personal digital assistant (PDA), an electronic notepad and a cellular phone. The keyboard includes a plurality of key elements that are arranged in an array, and a user inputs desired information to the electronic equipment by pressing the key element with a finger or the like.
Although the keyboard includes a plurality of key elements arranged at prescribed intervals, users to operate the keyboard have different shapes of hands and different habits of operation and so on. In light of this, a keyboard with the variable pitch of key elements to thereby offer optimum usability for each user has been invented.
Japanese Unexamined Patent Application Publication No. 2006-309689 discloses a variable key pitch keyboard that includes a plurality of key rows each having a plurality of integrated key elements arranged in the vertical direction of the keyboard so that the pitch of each key row is variable using a plurality of gears and a plurality of racks.
In this keyboard, a plurality of gears that are engaged with each other are placed along the central axis at the central part in the transverse direction of the keyboard, and two racks are placed from each gear to two corresponding key rows arranged with respect to the central axis as a symmetry axis. Each gear has a larger gear diameter as a distance from the central axis to a corresponding key row is longer. When a given key row shifts to the right, for example, the rack placed across the shifted key row shifts in conjunction therewith, and the gear engaged with the rack thereby rotates. In conjunction with the gear, the other corresponding rack causes the other corresponding key row to shift to the left. Further, another gear engaged with the gear rotates in conjunction therewith, causing the other rack engaged with the other gear to shift. Accordingly, when a given key row shifts, the other key row can shift with the shift amount of the key row adjusted according to a distance from the center axis.